The Reef

“The enormous size and diversity of the GBR (Great Barrier Reef) means it is one of the richest and most complex natural ecosystems on earth, and one of the most significant for biodiversity conservation.”

The Great Barrier Reef, a reef of such immense proportions that it can be seen from space, all 2,300 kilometres of it, encompassing its 2,900 individual reefs and 940 islands and cays (WWF Australia, n.d.). Every single rock, every coral polyp and every fish whether great or small is a part of this one, massive living thing.

This page is dedicated to an overview of the overwhelming biodiversity of the Great Barrier Reef. Click on a sub-page below to begin your journey into the vast array of creatures both familiar and not-so-familiar, all of which inhabit and constitute the Great Barrier Reef.

Welcome to ‘Save the Reef’!

This is a site centred on the issues, strategies and problems surrounding the conservation and preservation of the Great Barrier Reef, listed as a world heritage site by UNESCO for outstanding universal value. Use the navigation tabs above to get around or jump straight to a category and its attached articles using the drop-down menu directly below. If you can't find what you're looking for, try the search function: it's the little magnifying glass icon just on the top right.

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Disclaimer:

Every effort has been made to ensure the accuracy of the information supplied in these pages, and to the best of the blogger’s knowledge, beliefs, and opinions. However, the blogger is conscious that there may be unintentional errors or omissions, and he is not liable for any unintentional errors or omissions. Neither Nanyang Technological University (NTU) nor the School of Humanities and Social Sciences (HSS) assumes any liability for errors or omissions, or for damages resulting from the use of the information contained herein, and are not responsible for the content of external internet sites.The information in these pages is provided on the basis that the reader will not rely on it as the sole basis for any action or decision. Readers are advised to contact the stated primary source or its originating institution before acting on any of the information provided.

Conservation and Preservation of the Great Barrier Reef

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The process of coral bleaching appears horrifying. Imagine an entire plain of multicoloured coral turning ghostly white all at once. According to the National Geographic (2010), the Caribbean has lost around 90 percent of its coral reefs, with half of all the corals lost due to bleaching (National Oceanic and Atmospheric Administration, 2014).

“When corals are stressed by changes in conditions such as temperature, light, or nutrients, they expel the symbiotic algae living in their tissues, causing them to turn completely white.”

Coral bleaching occurs naturally when environmental conditions change, such as an increase in water temperatures (National Geographic, 2010). Like an aircraft forced to dump excess weight in an emergency, coral polyps evacuate the symbiotic zooxanthellae that live inside them. The measure does seem extreme, but there is evidence to suggest that bleaching could be a sly way of ensuring the coral’s own survival in the long run: by expelling algae that will not be able to withstand whatever environmental changes that elicited the bleaching, the coral make room for algae that could be more hardy than their previous zooxanthellae residents (National Geographic, 2010). Although the process is geared to help the coral survive, it it does make the coral more vulnerable to perishing (NOAA, 2014), along with ridding it of the colourful, life-giving zooxanthellae that reside in the coral polyps and provide energy for the coral through photosynthesis.

With human-driven climate change showing no signs of stopping, it is expected that coral bleaching will continue at an increasingly unhealthy rate. And to make matters worse for the coral of the Great Barrier Reef and other reefs around the world, another threat looms large: the crown of thorns starfish.

The menacing-looking crown of thorns starfish (or COTS, for short), unlike coral bleaching, really is as scary as it looks, and it is obvious from the first glance how the COTS got its name. The COTS is a large species of starfish, often reaching sizes of up to a full metre across, armed with anything from 7 to 23 arms bristling with venomous spines.

A starry pufferfish (Arothron stellatus), one of the few living things brave enough to take on a mature COTS. (http://www.chessington.com/explore/sea-life-centre/attraction/114/starry-pufferfish.aspx)

The COTS also has very few natural predators once it has reached maturity (although it probably has some of the weirdest predators, such as the Starry Pufferfish and the Triton’s Trumpet snail, seen devouring a COTS here). COTS larva, on the other hand, are more vulnerable to being consumed by a wider range of aquatic life, anything from crustaceans to fish (ARKive, n.d.).

Seemingly to counter this, female COTS can carry up to 60 million eggs at once (ARKive, n.d.). Multiple starfish also coordinate their spawning (just like coral do) to increase reproductive success. COTS populations can also see sudden growth spurts known as outbreaks. The sheer number of eggs one female carries means that even small populations of starfish can quickly repopulate and far exceed their previous numbers and spells disaster for coral. (ARKive, n.d.)

COTS outbreaks have been naturally occurring on the Great Barrier Reef every so often (Great Barrier Reef Marine Park Authority, n.d.). However, once again due to human-related factors, a natural process now runs rampant and out of control. As with eutrophication (discussed in the post immediately prior), COTS outbreaks are affected by nutrients in the water. A study on the decline of coral cover in the Great Barrier Reef conducted by De’ath, Fabricius, Sweatman and Puotinen (2012) states that “water quality affects the frequency of COTS outbreaks in the central and southern GBR (Great Barrier Reef)”. What these scientists found is that nutrient-rich waters facilitated the growth of phytoplankton, which the larva of COTS feed and thrive on. Coupled with the already impressive reproductive capabilities of the starfish and the increasing frequency of outbreaks (De’ath et al., 2012), and it is clear that human activity is worsening the situation for the Reef.